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971.
网络文化背景下教育特性的全新思考   总被引:3,自引:0,他引:3  
胡凡刚 《齐鲁学刊》2001,(6):141-144
网络文化与教育是双向互动的关系,网络文化背景下的教育应具有广泛性和平等性、科学性和人文性、个性化和创新性、终身性和全息性、国际性和民族性。  相似文献   
972.
诚信之于人的作用可以从人格的进路上予以见证。正义是古希腊文化的四主德之一,是基于诚信的法律秩序,正义人格就是以理智控制情感和欲望,保证心灵和体质的健康。君子人格是中国传统儒家文化的核心内容,是人的自觉的道德要求和积极的境界展现。儒家诚信之德的现代意义主要表现在它是不同文化进行对话的平台,是社会主义和谐社会建设的思想因子,是贯彻科学发展观的内在来源,在建设社会主义核心价值体系中发挥基础性作用。  相似文献   
973.
提出一种新的平均频率合成技术,给出了两种较实用的实现方法。平均频率合成技术的特点是瞬时频率不稳定,而平均频率的误差很小。平均频率合成器具有电路简单及换频方便、快捷的优点。文中给出的分频法平均频率合成器已成功地用于作者所设计的B超仪中。  相似文献   
974.
We develop statistical testing methodology for closely spaced spectral lines based on multitaper spectrum estimates and apply it to a time series of solar magnetic field magnitude data recorded by the Ulysses spacecraft. The test is formulated through complex-valued weighted least squares. Using this test in combination with the test for well-separated lines, we can accurately detect the solar equatorial rotation frequency of the sun, and its harmonics, from data recorded by Ulysses's magnetometer at solar mid-latitudes; this is a potentially important result for solar physicists, since it has implications for the structure and dynamics of magnetic fields in the solar corona.  相似文献   
975.
The conventional Cox proportional hazards regression model contains a loglinear relative risk function, linking the covariate information to the hazard ratio with a finite number of parameters. A generalization, termed the partly linear Cox model, allows for both finite dimensional parameters and an infinite dimensional parameter in the relative risk function, providing a more robust specification of the relative risk function. In this work, a likelihood based inference procedure is developed for the finite dimensional parameters of the partly linear Cox model. To alleviate the problems associated with a likelihood approach in the presence of an infinite dimensional parameter, the relative risk is reparameterized such that the finite dimensional parameters of interest are orthogonal to the infinite dimensional parameter. Inference on the finite dimensional parameters is accomplished through maximization of the profile partial likelihood, profiling out the infinite dimensional nuisance parameter using a kernel function. The asymptotic distribution theory for the maximum profile partial likelihood estimate is established. It is determined that this estimate is asymptotically efficient; the orthogonal reparameterization enables employment of profile likelihood inference procedures without adjustment for estimation of the nuisance parameter. An example from a retrospective analysis in cancer demonstrates the methodology.  相似文献   
976.
The problems of estimating the reliability function and Pr{X1+...+Xk ≤ Y} are considered. The random variables X’s and Y are assumed to follow binomial and Poisson distributions. Classical estimators available in the literature are discussed and Bayes estimators are derived. In order to obtain the estimators of these parametric functions, the basic role is played by the estimators of factorial moments of the two distributions.  相似文献   
977.
In this paper, we consider chain ratio and regression type estimators for estimating median in survey sampling. We find expressions for the variance of the chain-ratio and chain-regression type estimators considered in the present investigation. The optimum values of the first phase and second phase sample sizes are also obtained for the fixed cost of survey. The relative efficiency of chain-ratio and chain-regression type estimators have been studied in comparison to ratio and regression type estimators of median proposed by Singh, Joarder and Tracy (2001).  相似文献   
978.
A first-order random coefficient integer-valued autoregressive (RCINAR(1)) model is introduced. Ergodicity of the process is established. Moments and autocovariance functions are obtained. Conditional least squares and quasi-likelihood estimators of the model parameters are derived and their asymptotic properties are established. The performance of these estimators is compared with the maximum likelihood estimator via simulation.  相似文献   
979.
研究数据对参数估计的影响是一个重要的问题。找出那些对回归分析影响很大的数据是非常有理论价值和应用价值的。本文主要介绍这方面的基本结果。  相似文献   
980.
Two fractional factorial designs are isomorphic if one can be obtained from the other by reordering the treatment combinations, relabelling the factor levels and relabelling the factors. By defining a word-pattern matrix, we are able to create a new isomorphism check which is much faster than existing checks for certain situations. We combine this with a new, extremely fast, sufficient condition for non-isomorphism to avoid checking certain cases. We then create a faster search algorithm by combining the Bingham and Sitter [1999. Minimum aberration fractional factorial split-plot designs. Technometrics 41, 62–70] search algorithm, the isomorphism check algorithm of Clark and Dean [2001. Equivalence of fractional factorial designs. Statist. Sinica 11, 537–547] with our proposed isomorphism check. The algorithm is used to extend the known set of existing non-isomorphic 128-run two-level regular designs with resolution ?4?4 to situations with 12, 13, 14, 15 and 16 factors, 256- and 512-run designs with resolution ?5?5 and ?17?17 factors and 1024-run even designs with resolution ?6?6 and ?18?18 factors.  相似文献   
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